Battery Pack Disassembly

Once we finally made it back from North Carolina, we needed to unload the batteries. While we had a forklift to LOAD the batteries, we didn’t have one at my place and had to resort to an engine hoist, furniture dollies, and finally, steel pipes.

Getting 2,000 pounds of batteries off the trailer was no easy task. They don’t have any lifting eyes, nor are there even spacers under the boxes to make it easy to slide a strap under. We eventually got them off the trailer. The driveway was too rough for the furniture dollies, or even the wheels of the engine hoist. What ended up working the best was to place the battery boxes on steel pipes and then push and pull them with my electric lawn tractor.

The next day, I could start the process of opening up the boxes, seeing what’s inside, and removing the cells.
I opened the first box, the driver side battery, to figure out how it all worked. Then I filmed taking apart the passenger side battery box.

In each of the two boxes are two layers of 12 Valence lithium batteries, for a total of 48. Those batteries are rated at 12.8V, 138AH, 1766WH. Altogether, that’s a faceplate capacity of over 80kWh!

I set to work disassembling the battery pack. First, I had to remove all the stainless steel bolts around the edge of the box. Once that was done, I slid a pry-bar inside to break the seal. I needed to disconnect a few wires in the end from the inside before I could remove the lid of the box.

With the lid removed, I could finally see the Battery Management System (BMS), contactors, and the other balance of system components.

Of course, I used my multimeter to check the various connections before touching or disconnecting any components. Once I made sure I was working safely, I unbolted any cables holding this top layer over the batteries. Then the top layer was removed.

Now at the battery layer, I could see all the BMS and inter-cell connections. I snipped the zip ties holding some of the cables to each other, unplugged the BMS cables, and set to work removing the cables between the batteries.

I really like the style of terminal used on these batteries. A plastic-headed bolt threads down into the battery. As it does, it completely covers the terminal and battery cable. Only a tiny hole in the middle is still conductive. Perfect as a test point for a volt-meter. This is a great safety feature as there are essentially no places to accidentally cause a short. (Of course, always follow best practices, no matter what when it comes to high voltage DC!)

With all the battery cables disconnected, I could simply lift out the batteries one at a time.

For the bottom layer of batteries, it was essentially the same – just disconnect all the cables, and lift the batteries out.

We now have 80kWh of lithium batteries to use for solar backups and off-grid power, DIY electric vehicles, and anything else!

Until next time, Stay charged-up!
-Ben Nelson

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